An ecological metacommunity can be described in a literal sense as a community of ecological communities. More formally, a metacommunity is defined as a set of local communities that are linked by dispersal of multiple, potentially interacting species. The term is derived from the field of community ecology, which is primarily concerned with patterns of species distribution, abundance and interactions.

There are four theoretical frameworks, or unifying themes, that each detail specific mechanistic processes useful for predicting empirical community patterns. These are the patch dynamics

Patch dynamics

Patch dynamics is a conceptual approach to ecosystem and habitat analysis that emphasizes dynamics of heterogeneity within a system ....

, species sorting

Species sorting

Species-sorting , is an that approach builds on theories of community change over environmental gradients and considers the effects of local abiotic features on population vital rates and species interactions...

, source-sink (or mass effect) and neutral model frameworks. Patch dynamics models describe species composition among multiple, identical patches, such as islands, and emphasizes colonization-competitive ability trade-offs. Species sorting models describe variation in abundance and composition within the metacommunity due to individual species responses to environmental heterogeneity, such that certain local conditions may favor certain species and not others. This model represents the classical theories of the niche-centric era of G. Evelyn Hutchinson

G. Evelyn Hutchinson

George Evelyn Hutchinson FRS was an Anglo-American zoologist known for his studies of freshwater lakes and considered the father of American limnology....

 and Robert MacArthur

Robert MacArthur

Robert Helmer MacArthur was an American ecologist who made a major impact on many areas of community and population ecology....

. Source-sink models describe a framework in which dispersal and environmental heterogeneity interact to determine local and regional abundance and composition. This framework is derived from the metapopulation

Metapopulation

A metapopulation consists of a group of spatially separated populations of the same species which interact at some level. The term metapopulation was coined by Richard Levins in 1970 to describe a model of population dynamics of insect pests in agricultural fields, but the idea has been most...

 ecology term describing source-sink dynamics

Source-sink dynamics

Source-sink dynamics is a theoretical model used by ecologists to describe how variation in habitat quality may affect the population growth or decline of organisms....

 at the population level. Finally, the neutral perspective describes a framework where species are essentially equivalent in their competitive and dispersal abilities, and local and regional composition and abundance is determined primarily by stochastic

Stochastic

Stochastic refers to systems whose behaviour is intrinsically non-deterministic. A stochastic process is one whose behavior is non-deterministic, in that a system's subsequent state is determined both by the process's predictable actions and by a random element. However, according to M. Kac and E...

 demographic processes and dispersal limitation. The neutral perspective was recently popularized by Stephen Hubbell following his groundbreaking work on the unified neutral theory of biodiversity

Unified neutral theory of biodiversity

The unified neutral theory of biodiversity and biogeography is a hypothesis and the title of a monograph by ecologist Stephen Hubbell...

.